<template>
  <div>
    <span>全选:</span>
    <input v-model="isAll" type="checkbox" />
    <button @click="fan">反选</button>
    <ul>
      <li v-for="(item, index) in arr" :key="index">
        <input v-model="item.c" type="checkbox" />
        <span>{{ item.name }}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: [
        {
          name: "猪八戒",
          c: false,
        },
        {
          name: "孙悟空",
          c: false,
        },
        {
          name: "唐僧",
          c: false,
        },
        {
          name: "白龙马",
          c: false,
        },
      ],
    };
  },
  methods:{
fan(){
  this.arr.forEach((item)=>{
   return item.c=! item.c
  })
}
  },
  computed: {
 isAll:{
   set(val){
 this.arr.forEach(item=>{
  return item.c=val
 })
   },
   get(){
    return this.arr.every((item)=>{
     return item.c
     })
   }
 }
  },
};
</script>